Hydraulically actuated pump



July 6, 1965 F. J. KLEMPAY HYDRAULICALLY ACTUATED PUMP 2 Sheets-Sheet 1Filed sept. 1o, 1965 wf @y July 6, 1965 F. J. KLEMPAY 3,192,865

HYDRAULICALLY ACTUATED PUMP Filed Sept. l0, 1963 2 Sheets-Sheet 2 FIG. 5

INVENTOR Unid states Patent o 3,192,865 HYDRAULICALLY ACTUATED PUMPFrancis J. Klempay, 5635 Tippecanoe'Road,

Canfield, Ohio Filed Sept. 1l), 1963, Ser. No. 307,961

12 Claims. (Cl. 10S-152) This invention relates to improved andsimplified apparatus for pumping fluids by the use of hydraulic powersuch as, for example, a ow of hydraulic fiuid from Aa gear or vane typepump. More particularly, the invention relates to a double-actingdiaphragm'type of pump in which the forced displacement in the pumpingchambers is effected directly by the ow of hydraulic fluid underpressure from a suitable source, and also to an improved automaticvalvingmechanism for reversing the flow of the uid through the opposingmotor chambers thereof in a cyclic manner to effect substantiallycontinuous output from the pumping chambers of the assembly.

A principal object of the invention is the provision of apparatus of thekind and for the purpose stated which is compact in design, readilyportable,` and capable of being manufactured and assembled rapidly andeconomically whereby the range of usefulness ofk pumps of this kind isgreatly extended. Being of the diaphragm type, these pumps are wellsuitedV for handling abrasive and corrosive fluids, such as agriculturalsprays,lmeat curing liquids, sulphurous mineV waters, and variouslchemical solutions, and accordingly, another general object of theinvention is to improve the capacity, dependability, outputcharacteristics, and adaptability of pumps of this character, wherebythey may find practical and advantageous use for these and otherpurposes.

A more specific object of the Vinvention is the provision of adouble-acting diaphragm type of direct hydraulic powered fluid pump ofan arrangement for utilizing long-stroke flexible diaphragms forseparating the powering uid from the fiuid being pumped wherebyincreased pumping capacity may be attained in a unit of small overalldimension and whereby the frequency of output pressure drop, as occursat the end of each stroke, is substantially lowered.V

A further object of the invention is the provision of an improved casingstructure for apparatus of the kind described, whereby a minimum numberof separable parts arerequired and whereby manufacturing and assemblingof the apparatus is greatly facilitated. Thus, in accordance with thisaspect of the invention, the twoopposing pumping chambers or cylindersrequired are incorporated in a single length of steel tubing Whichcontains all the expansive forces generated by the high fluid pressuresinvolved. The passages and valves required for the powering fluidas wellas for the luid being pumped are all assembled in and on separatecomponents which are easily slid into the tubing and secured therein.

Another object of the invention is the provision of an improved andexceedingly simple automatic reversing valve for cyclically reversingthe direction of flow of hydraulic fluid under pressure through a pairof pressure chambers which may be advantageously employed in apparatusof the character described to achieve dependability in operation, longlife, high operating pressures, and reduced intervals of pressure dropat the end of each stroke. by a specially devised four-way valvemechanism which is operative to fully reverse the flow of uid upon verysmall movement of the principal valve part and which operates in a veryquick manner so that the time required to transfer the fluid pressurefrom one motor chamber .to the other and vice Versa is very minute.

The last named characteristic is achieved "ice Since this minute timeinterval is only a very small part of the total cycle of operation, byreason of the longstroke diaphragms employed, the mean effective outputpressure of the pump is only slightly below the maximum pressurepotential as determined by the capacity of the hydraulic uid source orby the setting'of the output relief valve associated with the pump ofthe invention. Likewise, the volumetric efficiency of the apparatus isvery high.

The Vabove and other objects and advantages of the invention willbecome, apparent upon consideration of the following specification andthe accompanying drawing wherein there is disclosed a preferredembodiment of the invention. f

In'the drawing:

FIGURE l is a longitudinal section through a pumping assemblyconstructed in accordance with the principles of the invention; Y

FIGURES 2 and 3 are transverse sections taken along the lines II-II andIII-III, respectively, of FIGURE l; and

FIGURES 4 and 5 are fragmentary sections taken Valong the lines IV-IVand V-V, respectively, of FIG- URE 3.

Referring to the drawing, the pumping mechanism `of the invention isassembled in a length of steel tubing 10 which is preferably seamlesssteel accurately bored and honed on its inner surface. Slideablyreceived Within the tube 10y and secured centrally therein by the capscrews 11 is a thick disc 12 having an annular recess 12 at each of itsends. Disc 12 is formed with a first eccentric thru-opening 13 which, aswill be explained below, constitutes the outlet ports of a four-wayvalve built into the structure, and opening 13 communicates with aradial threaded aperture 14 aligned concentrically within an aperture 15formed in the tube 10. It should be obvious that a suitably threadedconduit may be connected to the bore 14 to convey hydraulic Oil back toVa pump or reservoir, not shown, after the disc 12 is once properlylocated in the tube 1li.

y A second and larger thru-opening 16 is formed in the disc 12 in spacedrelation to the opening 13 and in communication with a second threadedradial bore 17 which extends to the outer periphery of the disc. In amanner to ,be later described, the opening 16 constitutes the inletports of the aforementioned four-Way oil valve. A third axialthru-opening 18 is formed in the disc 12 at the center of the disc andthis latter opening may or may not be in communication with the opening16. In actual practice, the end faces of the disc 12 are ma- :hinedflat, parallel, and smooth, and overlying the opposite faces in theregion of the openings 16 and 18 are plates 19 which are clamped to thedise by the bolts 20. VPlates 19 are apertured to receive the shoulderedend portions of a bushing 21, and it should be apparent l* that theplates 19 hold the bushing 21 rigidly against radial and axial movement.

Slideably received in the bushing 21 is a rod 22 which is shouldered ateither end to receive, first, a flat sheet metal disc 23, the flat endwall 24 of a sleeve-type of flexible diaphragm 25, and the flat bottomwall 26 of an outwardly facing cup-shaped piston member 27. The parts23, 24 and 26 are rigidly secured against the shoulder on the rod 22 bya nut 28. Diaphragms 25 are phragm sleeves 25 is chosen not only for itsoil resistance but also for its resistance to the kind f Huid to bepumped by the assembly. The members 27 have cylindrical side surfaces3i) over which the side walls of the diaphragms 25 Iroll uponlongitudinal movement of the members 27 in the tube 10. Y

Concentrically within the axial projection of opening 16 the plates 19each have a pattern of holes consisting of a centrally disposed hole 31surrounded` by a concentric circle of holes 32. Slideably received inthe holes 31 is a pin 33 on which is mounted an annular magnet 34. Thelatter is of the permanent type, preferably alnico, and is niagnetizedin a diametrical direction so that it will have maximum adherence toeither of the plates 19 when in contact therewith, it being understoodthat the plates 19 are formed of highly magnetic material such as softiron or low carbon steel. The pin 33, however, is preferably made ofnon-magnetic material such as brass. The pin 33 is brazed or sweatedinto a central bore formed in the magnet 34 during its manufacture sothat the magnet and pin always move as a unit. Magnet 34 has smooth andparallel end faces for fluid-tight engagement with the inner surfaces ofthe plates 19. An annular groove is formed in either end portion of thepin 33, and held by each of these grooves is a curved leaf spring 35. Asshown in FlGURE 3, the springs 35 are slit so that they may be simplysnapped onto the pin 35 at the time of assembly as will Vbe understood.For a purpose to Vbe later described, the free ends of springs 35project outwardly beyond the ends of the pin 33, as shown in `FIGURE 5.

Carried by the free ends of a pair of leaf Vsprings 36 is a pin 37 whichextends concentrieally through the bore 13 in the disc 12. Springs 36are mounted on the disc 12 by means of screws 38 and are slit at theirfree ends to snap onto the pin 37, the pin 37 being formed with annulargrooves for this purpose as shown'in FIG- URES 1 and 4. The pin 37carries intermediate the springs 36 a pair of valving elements eachcomprised of a disc 39 which is adapted to overlie an outer end face ofthe disc 12 and thus seal off one end of the bore 13.

From the above description, it will be apparent that there is provided apair of expansible chambers (A and B) separated by wall 12 and eachhaving an inlet and an outlet valve whereby while oil is being fed intoone chamber the oil in the other chamber may be exhausted. For a veryimportant reason as will appear hereafter, these valves areself-sealingin the manner of poppet valves-the loose connections andflexibility of the springs 36 permitting uniform setting about theentire peripheries of the valve discs 39 and the holes 31 being madesuiciently sloppy to permit the end faces of the magnet 34 to lie flatin uniform contact against the plates 19 under all conditions. Powerchambers A and B effect a reciprocating motion in the pistons 27 anddiaphragmsY 25 in the manner now to be described.

Assuming first that the interconnected pistons 27 are intermediate theends of their stroke and that the oulet and inlet valves are positionedas shown in FIGURES 4 and 5, respectively, it will be evident thatpressurized oil coming into the system through inlet port 17 will enterchamber 16 and then pass into chamber B through holes 32. The resultantpressure in chamber B will hold the right valve disc 39 tightly sealedand thereby move the pistons 27 to the right. Valve 34 remains seated bythis pressure and by magnetic attraction. The oil in chamber A will beforced out of the system past the left or open outlet valve disc 39 andthence through chamber 13 back to the pump or resrvoir through port 14.Springs 36 are rather light and serve only to bias the valve discs 39 toneutral positionsv where both are evenly spaced from their seats. As thepiston assemblies approach the right end of their stroke, as viewed inFIGURE 1, the disc 26 which is in chamber A contacts the spring 35,which is also in this chamber and a force is built up on the pin 33tending to unseat the magnet valve 34. However, because of magneticcontact and surface tension the magnet tends to stay put and adheres tothe adjacent plate 19. A considerable force is built up in the spring 35and eventually the adjacent disc 23 contacts the end of the pin 33 andnudges the same forwardly under force. As soon as contact between parts19 and 34 is broken the magnetic attraction as well as surface tensiondecreases precipitously and the energy stored in spring 35 snaps themagnetic valve 34 over to the other side in contact with the plate19-which is in chamber B. Immediately the holes 32 leading to chamber Bare sealed off and the oil now rushes into chamber A. Pin 37 is sodimensioned that it is also engaged by the disc 23 in chamber A to breakthe surface tension of the valve disc V39 in chamber B to permit thevalve discs 39 to instantly move to neutral positions during shifting ofthe magnetic valve 34 and the consequent momentary decreases of pressureof both chambers A and B. Thereafter the appear ance of increasedpressure in chamber A causes the valve disc 39 in chamber A to close andseat to seal this chamber A While permitting oil to be exhausted fromchamber B through the now open valve disc 39 which is in chamber B.

`In models actually constructed and tested, the above described sequenceof operation of the component parts takes place very rapidly at the endof stroke in either direction, causing only a momentary decrease inoutput of the pump even without the use of any accumulating devices.

Outwardly of the motor chambers A and B but yet within the tube 10 arethe pumping chambers C and D. These latter are sealed olf by plugs 40which are snugly received within the ends of the tube 10 and each ofwhich is formed adjacent its inner end with an annular groove 41 toreceive an O-ring seal 42. The plugs 40 are secured in position byradial cap screws 43 which extend through apertures formed in the tube10. Each of the plugs 40 is provided with an axial recess 44communicating with radial bores 45 and 46. A spring-biased outlet checkvalve 47 is built into bore 45 and a similar inlet check valve 48 isbuilt into bore 46, all as shown in FIGURE 2. The outer ends of thebores 45 and 46 provide threaded inlet and outlet ports 49 and 50,respectively, whereby the pump may be connected to output and inputconduits. It will be yunderstood that the tube 10 may be apertured orrelieved as shown at 51 in FIGURE 1 to permit these connections to bemade.

An important advantage of the specific embodiment of the .inventiondescribed above is that the reversing valve for the powering hydraulicfluid may be combined with (mounted in and on) the disc 12 as asub-assembly, and such sub-assembly may also include the diaphragms 25,pistons 27 and connecting rod 22. This greatly facilitates massproduction and assembly of the units, reducing their cost. Pistons 27may, if desired, be provided with ribs as shown to increase transfer ofheat from the powering uid which is preferably oil. All moving parts ofthe reversing valve are permanently bathed in the oil and consequentlyno appreciable wear of these vital parts takes place. Since the valveelements are self-sealing thin dimensions are not critical.

The pumping apparatus 'described above is essentially a double-actingpositive-displacement pump in which the seals for the movable walls ofthe compression charnbers, both for the hydraulic motive fluid and forthe fluid being pumped, is provided by the flexible diaphragm 25. Sinceall pumping pressures appear on both sides of these diaphragms, enormouspressures may be developed, lmited only by the pressure capacity of thehydraulic fluid pump employed. The only unbalanced pressure that canappear on these diaphragms is that of atmospheric on the suction strokeor that required to develop suicient force to overcenter ythe reversingvalve. Since in each side of the pump the pressure in `the motor chamberis always encaisse .Y slightly greater than the pressure in the pumping'chamber, the long-stroke diaphragms employed will always tend to roll inthe annular interstices between the piston skirts 30 and the adjacentcylindrical walls of the pressure chambers. Since these interstices maybe small in radial dimension and'since pressure differentials onopposite sides of the diaphragm-s 'are low, as explained, the diaphragmsare subjected only to low'tensile stresses and consequently, have longlife even though cheaply and inexpensively made.

It shouldfnot be apparent that I have provided improved hydraulicallyactuated pumping apparatus which accomplishes the objects initially setout. The apparatus is simple in principle, employs few parts which canreadily be produced by economical methods, and is extremely yrugged anddurable in operation even when pumping liquids at very high pressures.Since all movable parts of the motor section of the apparatus may bepermanently bathed in oil, lthere is very little wear in any of theparts and the operating eiciency is very high. It should be apparentthat the apparatusmay be mounted either close to or widely spaced fromthe hydraulic power. source employed, and that the apparatus may bepositioned either directly in a bath of the liquid being pumped or on oradjacent to a tank containing such liquid. This versatility is highlyadvantageous for many applications and, by selecting suitable materialsfor the walls of the pumping chambers land suitable inlet and outletvalve designs for the pumping chambers the apparatus may be adapted forpumping a wide variety of abrasive and/or corrosive materials. Fur-ther,since the physical size .of the apparatus is not lat all determinativeof its capacity the same may be scaled to fit in assemblies andenvironments not heretobefore considered available vfor pumpingapparatus.

The above specically described embodiment of the apparatus should beconsidered as illustrative only as many changes may be made thereinwithout departing from the principles of the invention disclosed. Forexample, the diaphragm walled compression chambers of the assembly mar,if desired, be replaced with conventional piston and cylinderassemblies, and other specic means than that shown herein may beemployed to snap the reversing valve in the motor section of theassembly from one of its opera-ting positions to the other and viceversa. An important 4aspect of the invention is thought to reside in thedevelopment of the simple snap-acting and .self-sealing four-way valvein the motor section of the `assembly incorporated entirely within thehydraulic uid stream without having any exposed par-ts. Reference shouldtherefore be had to the appended claims in determining the true scope ofthe invention.

Iclaim:

1. In a hydraulically lactuated diaphragm-type ii-uid pump a thickdisk-like moun-ting member having a cenltrally disposed axial boretherethrough, a rod passing through and slideably received in said boreand mounting 4at each of its ends a cup-shaped piston having its openend extending away from said mounting member, sleevelike flexiblediaphragms having ends secured in fluid-tight relation to the outerperipheral portion of said mounting member and having their outer endssecured to inner portions of said cup-shaped members in fluid-tightrelation thereto, a tube enclosing said diaphragms and pistons tothereby provide pumping chambers which are duid-tight with relation tothe pressure chambers encompassed by said diaphragms and existingbetween opposite sides of said mounting member and said pistons, andmeans to supply hydraulic fluid under pressure to said pressure chambersalternately while simultaneously exhausting hydra-ulic fluid from theopposite chamber.

2. Apparatus `according to claim 1 further characterized in that saidmeans comprises fluid inlet and outlet passages extending radiallyinward from the outer periphery of said mounting member, and furtherincluding a snap-acting four-way valve interconnecting said passages.and said pressure chambers and being carried by said mounting member,and means in said pressure chambers to operate said valve in responseVto movement of said rod and pistons.

`3. Apparatus according to claim 2 further characterized in that Ysaidfour-way valve comprises apair of spaced axial bores extending throughsaid mounting member and interconnecting intermediate their ends with`said inlet and outlet passages, respectively, valve elements slideablyreceived in said bores to close ott the ends thereof alternately, andmeans operated by said pistons to actua-te said Vvalve elements wherebysaid inlet passage is connected to one of said chambers while .saidoutlet passage is connected to the other of said chambers and viceversa.

4. A hydraulically Vpowered pump comprising ya unitary tube, atransverse wall in said tube intermediate the ends thereof, discs in theends of said tube to thereby form two longitudinally spaced `chambersseparated by said wall, a piston in each of said chambers to divide thesame into la power chamber adjacent said wall and a pump chamberadjacent one of said discs, a rod extending slideably through saidwallfor interconnecting said pistons, inlet and outlet passages for saidpump chambers in said discs, radially extending inlet and outletpassages for powering vloil in said wall, and a snap-acting four-wayvalveV assembly built into said wall and connected with the passages inthe wall for :reversing the iiow of powering oil through said powerchambers.

5. `In hydraulically. powered reciprocating vapparatus having a pair ofexpansible power chambers each having a movable outer end wall andseparated by a iixed barrier wall, a pair of spaced thru-bores in saidbarrier wall interconnecting said chambers and communicating,respectively, with an inlet passage and an outlet passage formed in saidbarrier wall, a valve element comprising a pair of discs spaced greaterthan the thickness of said barrier wall movable into alternateengagement with the opposite side surfaces of the barrier wall about thebore connected to the outlet passage to seal off alternate ends of thelast mentioned bore, apertured plates overlyingV said side surfacesabout the other bore, a second valve element in the form of a blockmovable in said other bore to seal ott the apertures in said platesalternately, and means driven by said movable outer end walls to actuatethe second of said valve elements, the other of said valve elementsmoving in response to the change in direction of fluid ow which resultsfrom movement of the said second valve element.

6. Apparatus according to claim 5 further characterized in that platesare formed of magnetic material, and

said second valve element being a magnet whereby said second elementwill always be attracted to one or the other of said plates.

'7. Apparatus according to claim 6 further including spring means tobias said first mentioned valve element to neutral position whereby bothof said discs are equally spaced outwardly from said side surfaces.

3. Apparatus according to claim 7 further including means for movingsaid iirst mentioned rvalve element by said movable outer end walls uponthe said end walls approaching said barrier wall.

`Si. In hydraulically powered reciprocating apparatus having a pair kofexpansi'ble power chambers each having a movable outer end Vwall andseparated by a ixed barrier wall, an opening through said barrier Wallinterconnecting said chambers, an apertured plate ofmagnetic materialclosing off each end of said opening, a magnet in said opening havingspaced end surfaces adapted to have alternate contact with the innerIfaces of said plates to seal off the apertures, an inlet passage insaid barrier wall leading to said opening, and means operated Vby saidouter end walls to bias said magnet into Contact with one or the otherof said plates.

10. In hydraulically powered reciprocating apparat-us having a pair ofexpansible power chambers each having a movable outer en-d wall andseparated'by a lixed barrier wall, an opening through said `barrier Wallinter,- connecting said chambers, a fluid passage in said barrier wallcommunicating with said opening, magnetic means forming a sealingsurface at either end of said opening, and a magnet structure slideablein said opening and having energized surfaces to contact said sealingsurfaces alternately whereby said structure is always biased to one oftwo positions so that a port interconnecting one of said chambers Withsaid passage is open while the port interconnecting the other of saidchambers with said passage is closed.

11. Apparatus of the character described having means comprising aseparating wall for providing a pair of adjacent pressure chambers andhaving valve means for reversing the flow of hydraulic Huid underpressure -into and out of said chambers, said valve means comprising apair of spaced thru bores in said wall, an inlet passage within saidwall communicating with the rst of said bores intermediate the endsthereof, van outlet passage in said wall communicating with 'the secondof said bores intermediate the ends thereof, valve elements slideablyreceived in said bores to close off the ends thereof alternately, andmeans in said chambers to actuate said valve elements whereby said inletpassage is connected to one of said chambers while said outlet passageis connected to the other of said chambers `and vice versa, the valveelement in the bore communicating with the outlet passage comprisingvalving discs separated by more than the thickness of said-wall andadapted to close onto kthe side surfaces of said wall to close oppositeends of the last mentioned bore alternately, apertured plates overlyingsaid side surfaces at thek ends of the other bore, and said valveelement in said other bore comprising a block of less thickness than thespace between said plates and slideable into alternate engagement withsaid plates, said plates being formed of -magnetic material and saidblock being a magnet `whereby said block moves 4from one plate to the-other with a Vsnap action.

12. Apparatus according to claim 11 furthe-1' including a spring at eachend of said block, and said means to actuate being positioned to engagesaid springs `and preload the same before the block is disengaged fromeither of said plates.

References Cited by the Examiner UNITED STATES PATENTS 821,926 5/06Cornish 230-l62 862,867 8/07 Eggleston 230-52 1,164,926 12/15 Clark103-51 2,644,477 7/53 King 261-65 2,679,209 5/54 Fischer et al 103-1522,798,440 7/57 Hall l03-152 LAURENCE V. EFNER, Primula Examiner.

ROBERT M; WALKER, Examiner.

1. IN A HYDRAULICALLY ACTUATED DIAPHRAGM-TYPE FLUID PUMP A THICKDISK-LIKE MOUNTING MEMBER HAVING A CENTRALLY DISPOSED AXIAL BORETHERETHROUGH, A ROD PASSING THROUGH AND SLIDEABLY RECEIVED IN SAID BOREAND MOUNTING AT EACH OF ITS ENDS A CUP-SHAPED PISTON HAVINNG ITS OPENEND EXTENDING AWAY FROM SAID MOUNTING MEMBER, SLEEVELIKE FLEXIBLEDISPHRAGMS HAVING ENDS SECURED IN FLUID-TIGHT RELATION TO THE OUTERPHERIPHERAL PORTION OF SAID MOUNTING MEMBER AND HAVING THEIR OUTER ENDSSECURED TO INNER PORTIONS OF SAID CUP-SHAPED MEMBERS IN FLUID-TIGHTRELATION THERETO, A TUBE ENCLOSING SAID DIAPHRAGMS AND PISTONS TO